Effect of pre-impingement length and misalignment in the hydrodynamics of multijet impingement atomization

The multijet impingement atomization strategy is proposed as a competitive one in designing atomizers with relatively simple geometries, producing sprays from the impact of multiple jets at low-flow rate conditions (<1.5 l/min). Most theoretical studies have been made for the spray produced by the impact of two jets. However, there are two important geometric issues related with the atomizer design, scarcely approached in the literature, which are the pre-impingement length of jets before impact and jet misalignment. This work analyses the influence of these parameters on the structure of the liquid sheet as well as on drop size. First, the liquid sheet structure has two hydrodynamic regimes: closed-rim and open-rim. The results evidence that higher pre-jet-impingement distances influence only the open-rim regime, namely, producing shorter liquid sheet breakup lengths, smaller drop sizes, and more droplets. The jet misalignment elongates the liquid sheet in the closed-rim regime, and anticipates breakup in the open-rim regime.